How This Artist Uses a Climate-Controlled Room to Make Indoor Clouds

It starts like a fog machine, deploying its vaporous mist into the air—until the cloud it emits holds its exquisite shape and silently hovers mid-room for hours. This is the drama and allure of Nimbus, the physics-defying work of Dutch sculptor Berndnaut Smilde.

As for how he actually does it, Smilde is a bit coy about the process:

“Moisture is the main factor, and if it’s cold, that really helps,” he explains. “Other than that, I’m using all kinds of means to create an image and idea.” Mostly, that entails fog machines and squirt bottles filled with water — and “shutting down the fire alarms,” he laughs, “otherwise everybody will get very wet!”

After the clouds, Smilde will focus on making rainbows, according to the Times: “a large-scale prism, filled with mineral oil, to be projected onto the Colorado Mountains once the birds of prey living in the forests are done breeding.”